ZCoin (XZC)
Basics * Mineable, Proof of Work algorithm by Lyra2z * Currency * According to CMC: "Zerocoin is a cryptocurrency proposed by Johns Hopkins University professor Matthew D. Green and graduate students Ian Miers and Christina Garman as an extension to the Bitcoin protocol that would add cryptographic anonymity to Bitcoin transactions. With Zcoin’s Zerocoin feature, only the sender and receive would be able to ascertain the exchange of funds in a given transaction, as no transaction histories are linked to the actual coins. Zcoin operates a multi-node model where mining nodes verify blockchain transactions and Znodes store blockchain data." * "Zerocoin as implemented by Zcoin uses a trusted setup performed by a third party in an academic challenge called the RSA Factoring Challenge in 1991 where the incentive to insert a backdoor is low and there was a sizeable bounty on it to break it. Although this is a decent implementation with a low chance of it being compromised, we believe the whole purpose of blockchain is to build systems that do not require trust, and that same principle applies to our privacy system as well. In fact, Zcoin’s initial release in 2016 was delayed as our founder Poramin Insom spent many months trying to remove trusted setup through the use of RSA UFOs which proved to be unworkable and had to settle for the RSA Factoring Challenge parameters." * Has Tor integration Zerocoin Protocol Vulnerability and Lelantus Future * Got a serious vulnerability back in 4-2019. It basically meant their protocol was broken and most projects utilizing Zerocoin stopped their private send functions afterwards. Projects affected were: ZCoin itself, PIVX, Veil, Gravity Coin, Navcoin (who was developing a Zerocoin variant called ZeroCT on their testnet) and NIX. On 19-4-2019 core developer Peter Shugalev found the root cause of the issue and confirmed that it was a failure in the cryptography of the Zerocoin protocol and that it affected all Zerocoin implementations. Forged coins were created, but not exceeding 1% of the circulating supply. The issue was not from a coding error, but from a cryptographic flaw in one of the proofs in the Zerocoin protocol that has existed since its inception. * Afterwards ZCoin decided (26-4-2019) to abandon the Zerocoin protocol. "Although we believe that Zerocoin can be fixed given sufficient time, we have decided not to dedicate further resources to it. This is in line with our roadmap to transition away from Zerocoin to Sigma, which has no trusted setup, security proofs for all its proof systems, and it has a much simpler construction along with its performance benefits." * From their website (20-3-2019): "Sigma is a precursor to our next gen privacy protocol Lelantus developed by our cryptographer Aram Jivanyan which further builds on Sigma and greatly expands its functionality and privacy features by removing the need for fixed denominations in minting and spending. Deploying Sigma gives us the necessary time to develop Lelantus properly while it undergoes academic peer review and further improvements." Team, investors, etc. * Poramin Insom; Founder, lead developer * Has a big Russian and Armenian team. * Peter Shugalev; core dev * Reuben Yap; first employee and community manager * Ian Miers, one of the authors of Zerocoin * Aizensou, dev * Tadhg Riordan, Developer * Snguyen, Developer * Aram Jivanyan; cryptographer * Andrey Bezrukov; C++ Developer * Hung Nguyen @ Herofire, Developer * + Zachary Diebold, Developer * + Sandra Yap, Media and Relations * + Sebastian Mack, Community Support * + Reuben Yap promoted to Chief Operating Officer * Tim Lee; first investor Category:Coins/Tokens